Actually, the firehouse looks pretty straight-forward, it only has two sound tracks, one for the truck going out, and one for the truck going in. A fairly simple sound board with two sound clips of your choice would probably do the trick here. I have made several sound modules with multiple selectable inputs, and I have one in process with totally isolated input triggers that would do this function very well.
Obviously, it would be a case where you'd have to dig into the firehouse to pick a trigger point or two.
